The issue has been contentious for months and has gained renewed attention since November, when a 10-member Project Sponsors' Council heard reports about third-party reviews of bridge studies performed by the Oregon and Washington transportation departments. The sponsors council is charged with the major decisions on the project, including whether it should have 8, 10 or 12 lanes. The twin bridges in place for I-5 over the Columbia have six total lanes.

Vancouver officials strongly support a 12-lane bridge, saying building a 100-year facility too small would be short sighted. Mayor Sam Adams has said he thinks a 10-lane bridge would meet the project's needs, and a 12 lane span would encourage too much driving and would be too costly.

Council President David Bragdon has said he's skeptical of the reviews and modeling assumptions used to forecast traffic on the bridge in coming decades, saying that similar estimates in the past underestimated how much traffic would use other highway widening projects around the nation. If a lot more people use the bridge than expected, Bragdon says, the region's freight artery could be thwarted even after spending $4 billion on the Columbia River Crossing project.

Others, including Metro Councilor Rex Burkholder and Portland City Commissioner Randy Leonard, say the modeling studies use the best available forecasting methods. Toll charges - if they're high enough - can also help prevent future congestion from clogging a new, wider bridge, they say.

The outcome of any vote or discussion today would be to advice Bragdon's vote at a March 6 meeting of the sponsors' council. The Portland City Council met on the issue last week, and expects to meet again Feb. 25 to decide how Adams should vote at the March 6 sponsors' council.